+++ /dev/null
-// Copyright ©2016 The Gonum Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package testlapack
-
-import (
- "fmt"
- "math"
- "testing"
-
- "golang.org/x/exp/rand"
-
- "gonum.org/v1/gonum/blas"
- "gonum.org/v1/gonum/blas/blas64"
-)
-
-type Dgehd2er interface {
- Dgehd2(n, ilo, ihi int, a []float64, lda int, tau, work []float64)
-}
-
-func Dgehd2Test(t *testing.T, impl Dgehd2er) {
- rnd := rand.New(rand.NewSource(1))
- for _, n := range []int{1, 2, 3, 4, 5, 7, 10, 30} {
- for _, extra := range []int{0, 1, 13} {
- for cas := 0; cas < 100; cas++ {
- testDgehd2(t, impl, n, extra, rnd)
- }
- }
- }
-}
-
-func testDgehd2(t *testing.T, impl Dgehd2er, n, extra int, rnd *rand.Rand) {
- ilo := rnd.Intn(n)
- ihi := rnd.Intn(n)
- if ilo > ihi {
- ilo, ihi = ihi, ilo
- }
-
- tau := nanSlice(n - 1)
- work := nanSlice(n)
-
- a := randomGeneral(n, n, n+extra, rnd)
- // NaN out elements under the diagonal except
- // for the [ilo:ihi,ilo:ihi] block.
- for i := 1; i <= ihi; i++ {
- for j := 0; j < min(ilo, i); j++ {
- a.Data[i*a.Stride+j] = math.NaN()
- }
- }
- for i := ihi + 1; i < n; i++ {
- for j := 0; j < i; j++ {
- a.Data[i*a.Stride+j] = math.NaN()
- }
- }
- aCopy := a
- aCopy.Data = make([]float64, len(a.Data))
- copy(aCopy.Data, a.Data)
-
- impl.Dgehd2(n, ilo, ihi, a.Data, a.Stride, tau, work)
-
- prefix := fmt.Sprintf("Case n=%v, ilo=%v, ihi=%v, extra=%v", n, ilo, ihi, extra)
-
- // Check any invalid modifications of a.
- if !generalOutsideAllNaN(a) {
- t.Errorf("%v: out-of-range write to A\n%v", prefix, a.Data)
- }
- for i := ilo; i <= ihi; i++ {
- for j := 0; j < min(ilo, i); j++ {
- if !math.IsNaN(a.Data[i*a.Stride+j]) {
- t.Errorf("%v: expected NaN at A[%v,%v]", prefix, i, j)
- }
- }
- }
- for i := ihi + 1; i < n; i++ {
- for j := 0; j < i; j++ {
- if !math.IsNaN(a.Data[i*a.Stride+j]) {
- t.Errorf("%v: expected NaN at A[%v,%v]", prefix, i, j)
- }
- }
- }
- for i := 0; i <= ilo; i++ {
- for j := i; j < ilo+1; j++ {
- if a.Data[i*a.Stride+j] != aCopy.Data[i*aCopy.Stride+j] {
- t.Errorf("%v: unexpected modification at A[%v,%v]", prefix, i, j)
- }
- }
- for j := ihi + 1; j < n; j++ {
- if a.Data[i*a.Stride+j] != aCopy.Data[i*aCopy.Stride+j] {
- t.Errorf("%v: unexpected modification at A[%v,%v]", prefix, i, j)
- }
- }
- }
- for i := ihi + 1; i < n; i++ {
- for j := i; j < n; j++ {
- if a.Data[i*a.Stride+j] != aCopy.Data[i*aCopy.Stride+j] {
- t.Errorf("%v: unexpected modification at A[%v,%v]", prefix, i, j)
- }
- }
- }
-
- // Check that tau has been assigned properly.
- for i, v := range tau {
- if i < ilo || i >= ihi {
- if !math.IsNaN(v) {
- t.Errorf("%v: expected NaN at tau[%v]", prefix, i)
- }
- } else {
- if math.IsNaN(v) {
- t.Errorf("%v: unexpected NaN at tau[%v]", prefix, i)
- }
- }
- }
-
- // Extract Q and check that it is orthogonal.
- q := blas64.General{
- Rows: n,
- Cols: n,
- Stride: n,
- Data: make([]float64, n*n),
- }
- for i := 0; i < q.Rows; i++ {
- q.Data[i*q.Stride+i] = 1
- }
- qCopy := q
- qCopy.Data = make([]float64, len(q.Data))
- for j := ilo; j < ihi; j++ {
- h := blas64.General{
- Rows: n,
- Cols: n,
- Stride: n,
- Data: make([]float64, n*n),
- }
- for i := 0; i < h.Rows; i++ {
- h.Data[i*h.Stride+i] = 1
- }
- v := blas64.Vector{
- Inc: 1,
- Data: make([]float64, n),
- }
- v.Data[j+1] = 1
- for i := j + 2; i < ihi+1; i++ {
- v.Data[i] = a.Data[i*a.Stride+j]
- }
- blas64.Ger(-tau[j], v, v, h)
- copy(qCopy.Data, q.Data)
- blas64.Gemm(blas.NoTrans, blas.NoTrans, 1, qCopy, h, 0, q)
- }
- if !isOrthonormal(q) {
- t.Errorf("%v: Q is not orthogonal\nQ=%v", prefix, q)
- }
-
- // Overwrite NaN elements of aCopy with zeros
- // (we will multiply with it below).
- for i := 1; i <= ihi; i++ {
- for j := 0; j < min(ilo, i); j++ {
- aCopy.Data[i*aCopy.Stride+j] = 0
- }
- }
- for i := ihi + 1; i < n; i++ {
- for j := 0; j < i; j++ {
- aCopy.Data[i*aCopy.Stride+j] = 0
- }
- }
-
- // Construct Q^T * AOrig * Q and check that it is
- // equal to A from Dgehd2.
- aq := blas64.General{
- Rows: n,
- Cols: n,
- Stride: n,
- Data: make([]float64, n*n),
- }
- blas64.Gemm(blas.NoTrans, blas.NoTrans, 1, aCopy, q, 0, aq)
- qaq := blas64.General{
- Rows: n,
- Cols: n,
- Stride: n,
- Data: make([]float64, n*n),
- }
- blas64.Gemm(blas.Trans, blas.NoTrans, 1, q, aq, 0, qaq)
- for i := ilo; i <= ihi; i++ {
- for j := ilo; j <= ihi; j++ {
- qaqij := qaq.Data[i*qaq.Stride+j]
- if j < i-1 {
- if math.Abs(qaqij) > 1e-14 {
- t.Errorf("%v: Q^T*A*Q is not upper Hessenberg, [%v,%v]=%v", prefix, i, j, qaqij)
- }
- continue
- }
- diff := qaqij - a.Data[i*a.Stride+j]
- if math.Abs(diff) > 1e-14 {
- t.Errorf("%v: Q^T*AOrig*Q and A are not equal, diff at [%v,%v]=%v", prefix, i, j, diff)
- }
- }
- }
-}